Manufacture of carbid.



No. 819,222. PATENTED MAY 1, 1906. H. ,L. HARTBHST'EIN.

MANUFACTURE OF GARBID.

APPLICATION FILED JULY 23. 1902. RENEWED SEPT. 30, 1905.

, is mixed with carbonaceous material, such ing is a specification.

an electric or other furnace and at a .high dethe cooled product finallyremoved, broken crudeness of former-methods, to utilize in the STATES PATENT OFFICE.

:. ASSIGNMENTS, TO ELECTRO CHEMICAL & DEVELOPMENT COMPANY, OF PIERRE, SOUTH DAKOTA, A CORPORATION OF SOUTH DAKOTA.

MANUFACTURE OF CARBlD.

Specification of Letters Patent.

Patented May 1, I906.

To all, whom it may concern:

. Be it known that I, HERMAN L. HARTEN- STEIN, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented anew and useful Manufacture of Carbid, of which the follow- This invention relates to the manufacture of carbid. w

The object of the invention is to produce carbid of a superior quality for commercial purposes and in a most simple, 'eflicient, and economical manner. 1

The invention consists, substantially, in the method of operation and procedure'hereinafter set forth and as illustratedin the accompanying drawing.

The single view of, the accompanying drawing illustrates ari apparatus adapted to the carrying out of m invention. l

According to tlie ordinary methods such as are commonly practiced in the manufacture of carbid for commercial purposes lime as coke, and the mixture is fused dr melted in 'gree of-temperature,. the molten mass being usually permitted to cool in the furnace,'and

up or crushed, packed, shipped; or used for use'in the manufacture of acetylene gas '01 for other method of operation is objectionable-inmany respects and results in the production of aniiifen'or grade or quality of finishedfproduct or carbid. I I It is among the-"purposes of my invention to simplify and improve the method of manufacturing carbid, gm avoid? the ,waste and most economical manner the-natural advan treatment and operation, and totake ever possible advantage of the condition in whic the material is placed by eachstep of the process inthe succeeding steps of operation.

, In carrying out my invention I propose to employ limestone. rather than lime, although in this respect I" do not desire to'be limited, as my invention contemplates many other advantages even when lime is used; but in the usual method of "burning lime'limestone in, lumps or in pieces ofvarious sizes is usedbee ing cha mto'ldln's with alternate layers of I well as a' waste of time and fuel.

fuel, an if:'tlie.;zcharges are;uneven or teo,

large the combustion is not perfect, hence resulting in imperfect burning of the stone, and consequently resulting in an inferior quality of lime, at least for the purpose of manufacturing carbid. Moreover, limestone in large and irregular-sized pieces causes loss of time in addition to being imperfectly burned, thereby necessitating a sorting of the stone and running of kiln for a time on one sizeand then for a -time' on another size, for if there is any very great variation in the size of pieces lumpsof stone being burned the time required to burn the larger-sized pieces is lost for Whatever percentage of small stones or pieces that may be present, besides involving an increased cost in the burning operation, as

lime is frequently produced crudely in imperfect or temporary kilns of various constructions, and consequently is not of the superior quality desired or desirable for carbid manufacture, and in some forms of kilns employed the limestone comes in contact with the fuel em and the resulting lime is injured by the ashes, frequently causing clinkers. In some forms of kilns gas is employed as the heating medium; but such kilns are usually of small capacity, inasmuch as the flame of the gas penetrates only a small distance through the .mass of stone being burned. Moreover, it usually requires many days bu-rnin to reduce the limestone to the proper con ition, and after the burning operation is completed the lime is permitted to cool down without in any other way utilizing the heat required during the burning operation, and tlnsis particularly true where the lime after being produced is transported to the point "of location of the lant in which carbid is manufactured. Again, whenlime is employed in the manufacture of carbid the lime'is crushed and pulveri-zed at the carbid plant previous to the operation of conversion, besides re uiring handling, and owing to its caustic qua ities it is very injurious to the life and health of the ,workme'n, as well as to near-by vegetation.

Moreover, as is well known, lime readily abe sorbs moisture and carbonic acid, and'when unduly exposed, as is frequently the case in the transportation and handling'thereof, it I causes ob ection'able irregularities-in the elec-- tri'c or other furnace in ,which the cmrversion HERMAN .L. HARTENSTEIN, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE Moreover,

loyed in the burning operation :ieefiected as, for instance, the blowing re.

sulting from the escape of carbonic-acid gas or carbon dioxid thereby wasting coke as well as the lime and also frequently clogging and hanging up the furnace charge. Again, in the ordinary method of manufacturing carbid the lime is usually mixed with the carbonaceous material in the cold, thereby necessitating mixing machinery, as well as the I labor and handling of the materials, and. also a very heavy electric current for effecting the fusing or melting operation, which is an expensive part of the operation. For these and other reasons which might be recited I prefer to employ limestone direct instead of lime in carrying my invention into practical operation, although, as above stated, I do not de sire to be limited or restricted in this respect. In carrying out my invention I propose to pulverize limestone and then to heat the same to incandescence in the presence of carbonaceous materialsuch, for instance, and

preferably, as pulverized coke, although other carbon-containing substances may answer the purpose. I therefore do not desire to be limited or restricted in this respect.

Generally speaking, and in its broadest terms, my invention ma be said to consist in crushing orp-ulverizing imestone, then heating the same to the point of incandescent-e in association with a carbonaceous substance,'

and then while in its heated condition supplying the charge to an electric or other furnace, where the mass is heated to the melting -p'oint to effect the desired conversionl into carbid, and finally tapping or running off the molten mass into molds or otherwise,

. carbid.

when the product is read to be broken up, crushed, packed, shippe or used for commercial purposes. After the charge of mixed limestone and carbonaceous substance has been suflieientl heated to expel the gases from the materials the heated charge may be delivered into a vat, reservoir, tank, or other suitable receptacle, from which said seated charge may be delivered to one or'more electric or other furnaces to be converted into In this manner I utilize as much as possible the heat unitsrequired in the preeating operation in raising and maintaining the temperature of the mass as delivered into the electric or other furnaces, thereby requiring less current in case of an electric furnace to effect the conversion of the mass into carbid. If desired, and preferably, I supply to the mass during the preheating operation a small portion of carb'id dust or fines, which is not suitable or desired for other use, in order to thoroughly expel and drive off any remaining carbon monoxid and carbon dioxid. The carbid dust or fines thus supplied during the preheating operation by means of the oxygen'contained'therein forms a superheating compound, and thereby serves to increase the temperature of the mass and .to enable the mass to retain its when deliver-ed into the distributing vat, reservoir, or

tank. I also attain the some object by adding as'uperheating compound to the heated mass during or immediately preceding the delivery of such mass into the distributing tank orwat. I have found that a composition composed of calcium carbid, sixty per cent, black oxid of manganese twenty per cent, (20%,) bituminous coal, lifteen per cent, (15%,) chlorate of potash, two per cent. (2%,) aluminium, three per cent, (3%,) answers the purpose of a superheating compound for my pur ose. I do not desire however, to be limite to any specific superheating composition or compound, as possibly other substances or compositions and other proportions of ingredients might equally well serve the desired purpose. The substances mentioned and the proportions set forth I have found to be efficient and satirfactory.

In the accompanying drawings I have illustrated an arrangement of appara tus adapted to the carrying out of the principles of my invention; but I desire it to be understood that my invention as herein claimed does not re side in the form of mechanism employed, the particular form shown being merely illustrative of an operative embodiment ofapparatus capable of performing my invention.

Reference-sign Adesignates a suitable hopper or bin 'adapted' to receive the limestone after being crushed and pulverized to the desired degree of fineness. I have found that limestone crushed to about twenty mesh Well answers my purpose; but my invention is not to be limited or restricted. in this respect, as other, degrees of fineness or coarseness might be employed. Reference-sign B des ign-ates a similar tank adapted to receive carbonaceous material in a finely-divided state as, for instance, crushed or pulverized coke. I have found coke desirable for my purposes, although it is obvious that other carbonaceous or carbon-containing substances may equally well answersuch, for instance, as charcoal, coal, lampblack, or the like. I have also found that the best results are obtained when the coke or carbonaceous substance is ground or pulverized to about fifty mesh or finer, though I do not desire to be limited in this respect.

C designates the preheating-furnace. This furnace may be of any suitable, convenient, or ordinary construction. In the form illustrated this comprises a rotary drum or cylinder adapted to receive rotation in any suitable or convenient manner-as, for instance, from the drivepulley D, through suitablyarranged gearing. The charges of pulverized limestone and carbonaceous material are delivered into the furnace C in any suitable or convei'iien't manner. Preferably and in the most economical arrangement the bins A B IOL' charges aredelivered or fed therefrom into the furnace C by gravity. If desired, the charges may be weighedas, for instance, by means of the automatic dumping-scales .E or otherwiseprevious to the introduction thereof into the furnace. Where av rotary drum is employed as a preheating-furnace,

. said drum may be rotated within a stationcoal being supplied in any suitable manner .from a conveniently-arranged bin G-as, for

ary sleeve, which sleeve communicates with the interior of the heating-drum .and with which sleeve connects suitable receiving and instance, by a suitably-arranged conveyer H-and the air-blast being supplied. in any convenient manner-as, for instance,from' a blower J. From the preheating furnace C the mass of material when raised to the desired degree of temperature is delivered into a distributing vat or tank K, from which such mass is delivered in a heated condition through one or more pipes L to the electric or other furnaces (indicated at M) for the conversion into carbid, the number of electric or other furnaces M depending upon the capacity of the plant, and the most economical arrangement is shown, wherein the pre- -heating-furnace C is located above the distributing vat or tank K and the latter is 10- the material is left by the preceding step of.

the operation. In other words, the heat required to calcine' the limestone 1n the preheating step of the process is practically all retained .in the materialfand particularly where a superheating substance, agent,'or compound is; employed in the manner above set forth, until such material is delivered into and is acted upon in the electric .or other furnace to effect the final step of conversion.

After the material has been reduced to molten condition in the electric or other furnace M it is tapped or runoff or otherwise delivered into molds or other suitable receptacles, and the process so far as the produc tion of carbid is concerned is com leted.

The operation is as follows: T e reheating-furnace C is first heated to a hig degree of tem erature-say 1,500 to 2,000 Fahrenheit rom the burner F. A char e of limestone, pulverized or granulated to t e des red degree of fineness, is then delivered into the preheating-furnace C after being wei hed, if desired. This charge is then agltated in any suitable manner-as, for instance, in the case of a rotary furnace, by imparting a slow rotation theretoand the temperature within the furnace increased until the charge is raised to the temperature of incandescence or thereabout. During this heating operation the carbonic-acid gas and other gases are driven off, and by agitating the chargeas,

for instance, by rotating the heater or fur-. nace-every particle of stone is acted upon by the heat. This operation requires a comparatively short time, and the degree of temperature maintained may be readily indicated by a pyrometer, and it may also be determined when the gashas been sufl iciently expelledas, for instance, by means of an ordinary gas-composometer. When this operation has been carried on to the desired extent,- the charge of pulverlzed or granulated carbonaceous material is delivered into the furnace and the agitation of the contents of the furnace continuedas, for instance, by rapidly rotating the same in case of "a rotary furnacethereby thoroughly mixing the carbon element with the heated limestone. In practice [employ limestone and coke in-about the proportion of three parts, by weight, of the stone to one part, by

weight, of the carbonaceous material. This proportion, however, may be varied without departure from the scope of my invention. Q

Sometimes a small percentage of phosphorus is present in limestone or lime, and which phosphorus is retained in the finished carbid. The presence of phosphorus in carbid is exceedingly objectionable on account of its inflammability and the danger of starting spontaneous combustion therefrom. In accordancev with my invention as. above explained the aluminium constituent of the superheating flux serves to drive off or expel any phosphorus that may be present in the mass under treatment. The proportion of superheating flux employed may be varied throughout a wide range and dependent upon the character or quality of limestone or lime-bearing ore or substance employed. Under ordinary conditions I have found the proportion of from fifteen to twenty pounds of superheating flux per ton of material treated satisfactorily answers the desired purpose. The operation is as follows: The limestone or lime-containing ore or substance (and preferably ina pulverized or granular condition) and also the carbonaceous material-such, for instance, as coke or the like (also preferably crushed orpulverized)are placed-in thereceiving-bins. Thepreheating-furnaceis then heated up to from 1,500 to 2,000 temperature. A charge of the crushed or pulverized limestone 1s then deliveiyd into the heated furnace, being previously weighed, if

a'very high degree of heat.

Ell:

desired, in the automatic scales. 'lFhe mass in the preheating-furnace is then suitably agitated-e tor instance, by slowly rotating the furnace, in case a rotary furnace is employedand the temperature thereof increased by properly regulating the supplyof coal and air through the burner or. otherwise to an extent such as to bring the limestone to incandescence. The charge of powdered carbonaceous material, previously weighed,

if desired, is. then introduced into the preheating-furnace and thoroughly mixed with the incandescent limestonein the presence of lhe superheating compound s then added to the mass, and immediately thereafter the mass is dumped or delivered into the distributing tank or vat. Ifdesired, the superheating compound may be supplied during the delivery of the heated mass into the distributingtank or the superheating compound may he placed in the distributing tank or vat andthe heated mass delivered therein. This compound or flux not only serves to retain" the high degree of heat of the mass while contained in the dis. tributing tank or vat, so that the mass is'distributed into the electric or other furnaces at a high temperature, but also this compound or flux tends to. drive on or expel any phosphorus that may be present. The heated mass, and while still in a highly-heated con dition. is distributed through the distributing vat or tankto the various electric or other furnaces in which the mass is subjected to the action of an electric current or otherwise heated to the fusing or melting point, and

the melted mass or carbid is then run off into molds or sheets'or otherwise and is ready to be Broken up, crushed, packed, shipped, or use From the foregoing description it will be seen that I provide an exceedingly simple, economical, and eflicient process for the man- 'ufacture of carbid, wherein the carbid is procining and mixing operations is retained in the mass until the mass is distributed to the electric or other fusing or meltin furnaces,

thereby re'quirin less current an involving less expanse to eil'ect the final. step'of melting or conversion into carbid. It will also be seen that I and enabled to produce a superior quality of carbid and a product iree from the presence of phosphorus'and the cost of manvastly reduced.

uiactiui'ngithe finished. product crcarbid is crease I do not claim herein the-superheating (1-- pound or composition of matter employed, as the same forms the subject-matter of a copending application executed oi even date herewith, Serial No. 116,665.

Having now set forth the object and nature of my invention and the manner of carrying the same into practical operation, What I claim as new and useful and of my own invention, and desire to-secureby Letters Patent. is-

1. In the manufacture of carbid, the procone which consists in calcining limestone in the presence of carbonaceous material, then adding to the calcined mass a mixture of cal cium carbid, black ox'id of manganese, bituminous coal, aluminium and chlorate of potash, to maintain the temperature .of the heated mass and to expel or drive off any phos-" phorus present therein, and finally fusing or melting the mass.

2. In the manufacture of carbid, the method which consists in calcining limestone in th'h presence of carbonaceous material, then adding to the heated mass a superheatin' flux, and finally subjecting the superheate mass to the fusing action of heat.

3. Inthe manufacture of carbid, the process which consists in mixing together pulverized limestone and carbon-containing substances, then preheating the mixture, then superheatingthe heated mixture to a state of incandescence, and finall fusing the mass. 4. In the manufacture o carbid, the process which consists in calcining limestone in thepresence of a carbon-0ontaining substance, then superheating the mass tomoan-- descence, andfinelly fusing the mass while in a heated state.

5. In the manufacture of car-bid, the rocess which consists in heating pulverized ime stone in the presence of pulverized coke, then superheating themixture to incandescence, and finally fusing the mass while in a highlyheated condition.

' 6. The method which consists in calcining limestone in the presence of powdered coke,

then adding a superheating flux to' the calcined mass while in a heated condition, and finally fusing'the superheated mass.

7. In the manufacture of carbid, the process which consists in. calcining pulverized limestone in the presence of carbonaceous material, and agitatmgthe mass during the calcining operation to efitect an intimate mixture ofthe elements, then superheating the calcined product to a stat'e'of incandescence,

and finally fusing the'superheated mass.

In witness whereof Ihave hereunto set my hand, this'Mth day of July, .1902, in the presence of the subscribing witnesses.

HERB/FAN L Harassme t Witnesses:

FRANK i. BRQWN, S. E. DARBY. 

